The shaman was the ranking medicine man, the ceremonial fetishman, and the focus personality for all the practices of evolutionary religion. In many groups the shaman outranked the war chief, marking the beginning of the church domination of the state. The shaman sometimes functioned as a priest and even as a priest-king. Some of the later tribes had both the earlier shaman-medicine men (seers) and the later appearing shaman-priests. And in many cases the office of shaman became hereditary.
Since in olden times anything abnormal was ascribed to spirit possession, any striking mental or physical abnormality constituted qualification for being a medicine man. Many of these men were epileptic, many of the women hysteric, and these two types accounted for a good deal of ancient inspiration as well as spirit and devil possession. Quite a few of these earliest of priests were of a class which has since been denominated paranoiac.
While they may have practiced deception in minor matters, the great majority of the shamans believed in the fact of their spirit possession. Women who were able to throw themselves into a trance or a cataleptic fit became powerful shamanesses; later, such women became prophets and spirit mediums. Their cataleptic trances usually involved alleged communications with the ghosts of the dead. Many female shamans were also professional dancers.
But not all shamans were self-deceived; many were shrewd and able tricksters. As the profession developed, a novice was required to serve an apprenticeship of ten years of hardship and self-denial to qualify as a medicine man. The shamans developed a professional mode of dress and affected a mysterious conduct. They frequently employed drugs to induce certain physical states which would impress and mystify the tribesmen. Sleight-of-hand feats were regarded as supernatural by the common folk, and ventriloquism was first used by shrewd priests. Many of the olden shamans unwittingly stumbled onto hypnotism; others induced autohypnosis by prolonged staring at their navels.
While many resorted to these tricks and deceptions, their reputation as a class, after all, stood on apparent achievement. When a shaman failed in his undertakings, if he could not advance a plausible alibi, he was either demoted or killed. Thus the honest shamans early perished; only the shrewd actors survived.
It was shamanism that took the exclusive direction of tribal affairs out of the hands of the old and the strong and lodged it in the hands of the shrewd, the clever, and the farsighted.